Anaerobic co-digestion of landfill leachate and sewage sludge: Determination of the optimal ratio and improvement of digestion by pre-ozonation
Journal Title: Environmental Health Engineering and Management Journal - Year 2024, Vol 11, Issue 1
Abstract
Background: Anaerobic co-digestion (AcoD) of various wastes is a suitable method for the removal of contaminants and biogas production. The first aim of this study was to determine the optimal ratio of landfill leachate (LL) and sewage sludge (SS) for AcoD, and the second one was to evaluate the effect of pre-ozonation of the mixture on AcoD. Methods: The LL and SS samples were taken from landfill sites and municipal wastewater treatment plants (MWTPs), respectively. In the first step, five reactors were used and named R1 (100% SS), R2(100% LL), R3 (15% LL/85% SS), R4 (25% LL/75% SS), and R5 (45% LL/55% SS). Mesophilic anaerobic digestion (AD) was performed on the reactors and the optimal ratio was determined. In the second stage, the optimal mixtures were subjected to an ozonation process before AcoD. Results: The results of the first stage showed that the highest efficiency removal of the total solids (TS), volatile solids (VS), and chemical oxygen demand (COD), and the highest biogas production belonged to R3 digester, containing 15% LL and 85% SS. In the second stage, the results showed that the removal efficiency of COD and VS in the ozonated sample at the dosage of 7.6 gO3/h were 29.8% and 36.6% higher than the non-ozonated sample, respectively. Furthermore, in the ozonated sample, the biogas yield and the content of methane in the gas mixture were 27% and 9% higher respectively, compared to the non-ozonated sample. Conclusion: According to the results, the appropriate ratio of LL to SS and pre-ozonation of LL/SS mixture have a great impact on the performance of AcoD.
Authors and Affiliations
Zahra Jamshidinasirmahale, Ahmadreza Yazdanbakhsh, Mohamadreza Masoudinejad, Nadali Alavi Bakhtiarvand
Keywords
Related Articles
- EP ID EP733005
- DOI 10.34172/EHEM.2024.11
- Views 9
- Downloads 0
Evaluation of landfill gas plant siting problem: a multi-criteria approach
Background: Landfill activities have environmental and economic values to a community. While the former deals with the control of landfill gas (LFG) emission into the atmosphere, the latter deals with the conversion of L...
Azo dye removal via surfactant-assisted polyvinylidene fluoride membrane
Background: Recently, concerns have been raised regarding the environmental and public health safety of azo dyes, the most widely used synthetic dyes. The membrane technique has been introduced as one of the efficient...
Removal efficiency of nitrate, phosphate, fecal and total coliforms by horizontal subsurface flow-constructed wetland from domestic wastewater
Background: Constructed wetlands are systems designed based on the utilization of natural processes, including vegetation, soil, and their associated microbial assemblage to assist in treating different types of wastew...
Root cause analysis (RCA), a little-known tool for medical errors pathology during the COVID-19 pandemic
This article has no abstract.
Optimizing functions of coagulants in treatment of wastewater from metalworking fluids: Prediction by RSM method
Background: Coagulation is a treatment procedure for metalworking fluids (MWFs). This study aimed to optimize coagulation using four coagulants and compare the results. Methods: In this research, the outputs of a coagul...